Retrieve Account Balance

curl --request POST \
  --url https://api.sand.getivy.de/api/service/balance/retrieve \
  --header 'Content-Type: application/json' \
  --header 'X-Ivy-Api-Key: <api-key>' \
  --data '{
  "currency": "EUR"
}'

{
  "balances": [
    {
      "currency": "EUR",
      "available": 123
    }
  ]
}